Bio 120 Final

What is radiometric dating?

the process of using radioactive isotopes within rocks to determine the age of something

How old is the earth believed to be

4.54 billion years

What is a geologic timeline?

can determine how long ago an organism lived by aging the rock fossils that are found within

gives us an idea of what lived when

What was Earth’s early atmosphere like?

very little oxygen, lots of hydrogen, ammonia, and methane

Why couldn’t earth sustain life until about 3.8 billion years ago?

was too hot- originally a ball of molten lava, but was then hit ny meterorites

What major even occurred that allowed eukaryotic life to begin and thrive?

oxygen became available

What is meant by extinction?

Elimination of all individuals in a species

How does extinction occur

it can be both sudden or gradual

What is adaptive radiation?

spreading out and diversification of organisms when they colonized a new habitat

What is punctuated equilibrium?

when extinction is followed by adaptive radiation

When do we most often see punctuated equilibrium?

when the environment changes

When did the dinosaurs thrive?

Mesozoic Era

What possibly lead to the dinosaurs extinction?

a 6 mile wide asteroid that smashed into the Yucatan Peninsula

What era concluded when the dinosaurs were wiped out?

Cretaceous Era

What era are we currently in?

Cenozoic Era

What era did birds, mammals, and flowering plants thrive?

the cenozoic era

What is biogeography and why is it useful?

can give us clues as to how species ended up where they are.

positions of landmasses are key

What was Pangaea?

one giant connected land mass that animals could roam across

What are plate tectonics?

caused land mass to split numerous times, forming continents

the movement of earth’s upper mantle and crust

How did the continents get to their current locations?

plate tectonics and the drift over time

What is taxonomy?

how scientists identify, name, and classify organisms based on shared traits

Why is taxonomy useful?

helps organize things

How many species have been classified?

8.7 billion

What group makes up the most species on earth?

invertebrates (i.e: insects)

What system of organization do we use to look at the similarities and differences between organisms?

DKPCOFGS

DKPCOFGS

Domain

Kingdom

Phylum

Class

Order

Family

Genus

Species

What two names make up the scientific name?

genus and species

What language is a scientific name in?

latin

What is the scientifc name of humans?

homo-sapiens

What is phylogeny?

relatedness between groups of organisms

What is a phylogenetic tree?

the organization system used to lay out what is related to what

like a family tree

What are the parts of a phylogenetic tree and what do they tell you?

1. Base (root)- common ancestor of all animals on tree

2. branches- seperate groups of ogransims that diverged from ancestors

3. nodes- common ancestor of all organisms ABOVE the location of node

4. tips of branch- most recent organisms of that lineage (can be extinct or living)

When did we first see ‘modern man’?

200,000 years ago

How much DNA do we share with all other human beings?

99.9%

What are some adaptions that humans have that able them to live virtually all over the globe?

African Descent- higher resistance to malaria; individuals with this allele survived, and passed it on to offspring who could survive in high areas of malaria.

European Descent- ability to digest milk easier; inicates that dairy products were probably important to survival in the past

Tibetan Descent- ability for red blood cells to carry oxygen more efficently; helps to compensate for low oxygen at high altitdues

How are some human adaptions better adapted to where they live?

skin color- evolved in response to different UV levels.

What is melanin?

a pigment produced with cells of our skin called maloncytes

lighter skin has less

darker skin has more

Why is melanin important?

our skin produces more as we are exposed to more sunlight

why our skin darken after being outside for a long period of time

Why do people closed to the equator have more melanin?

more exposure to sun and higher UV levels

What is vitiligo?

a long-term skin condition characterized by the appearance of white patches on the skin due to a lack of melanin, the pigment that gives skin its color

What is folate?

an essential water-soluble vitamin

What is Vitamin D?

a vitamin that builds bones and keeps them healthy

Where do we believe modern man first evolved?

africa

What do scientists call the woman to whom all humans can trace their ancestry?

Eve

What is mitochondrial DNA?

the DNA used to work our the human evolutionary tree

can be inherited from mom only

mtDNA

What is the “out of Africa” hypothesis?

humans orginated in africa, then migrated to other parts of the continent where their ancestors migrated to other parts of the continent giving rise to new Asians, Australians, and Europeans

What is a hominid?

any member of the family hominidae

humans, chimps, apes

humans and apes evolved from a common ancestor 13 million years ago

When did humans and chimps last share a common ancestor?

6 million yeras ago

What is ecology?

a huge discipline investigating how organisms interact with their living and non-living environment

can be:

• aquatic

• terrestrial

• landscape

• population

• community

What are abiotic factors?

entities without life

i.e: temperatures, pH, alkalinity, rainfall

What are biotic factors?

living entities

i.e: organisms and their interactions (competition, predators, reproduction)

What is an ecostyem?

all living organisms in an environment and the abiotic factors that they interact with

What is community?

populations of different species within a geographical area interacting with each other

What influences distributions patterns?

resources (food, water,ect) and interactions with other individuals

What are three distribution patterns often seen in nature?

random, clump, and uniformed

What is carrying capacity?

The maximum size of a population can sustain based on food supplyt and other resources

What is meant by population density?

nuumber of total organisms within given area

as population sizes increase, so does density and vice versa

Density-Dependent factors

factors whose influences on a population size and growth depend on number of individuals (density) and crowd

example: plant abundance

Density-Independent factors

factors that can populate growth regardless of population size or crowding

impact population regardless of density

examples: hurricane, tornado, weather

What is growth rate?

difference between the birth rate and the death rate of indivduals within population

two kinds:

exponential growth: rapid, unrestricted increases in population sizes. rare in nature, resources usually run out quickly, slwoing growth rate

logistic growth: pattern starts off fast, then tapers off as population reaches carrying capactiy

What is a carbon footprint?

how much greenhouse gas we produce

what are fossil fuels?

coal, natural gases, oil

use of these increases the amount of carbon dioxide in the atmosphere

what is deforestation?

destroys forests, which can no longer photosynthesize an capture CO2 from atmosphere

What is the greenhouse effect?

normal process in which heat from the earth is trapped by gases in the atmosphere

helps keep earth warm

what are greenhouse gases

gases that contribute to the greenhouse effect

carbon dioxide (CO2)

methane

when these gases increase, temperatures, increase

what is global warming?

increase in the earth’s average temperature

18 of last 20 years are warmest on record

What is meant by biocapacity?

the total natural resources and amount of wast it can asorb

Are we currently within earth’s biocapacity?

no, we are currently outside of it

what is sustainability?

living within earth’s biocapacity

what are some sustainable practices?

reducing usage of non-resuable resources (fossil fuels)

using renewable resources (water, wind, sunlight)

What is meant by an ecological footprint?

our demand on nature

ours us currently greater than earth’s capacity

What do the esophagus, stomach, small intestine, and large intestine of the GI tract do?

digestive system

What is a hormone and how does it work?

chemical messengers produced by the endocrine system that regulate various bodily functions

how do hormones get from place to place in the body

circulatory system and bloodstream

What are the different parts of the nervous system?

Central

• brain and spinal cord

Peripheral

• neurons outside of the central

• sensory division- fibers transmit impulses from receptors the central

• motor division- Fibers transmit impulses from central to effector organs

what are the functions of the skeletal system?

Force production for locomotion and breathing

Force production for postural support

Heat production during cold stress

What are the four chambers of the heart

2 upper atria (‘entry halls’)

• Receive blood from veins

• Right= Receives deoxygenated blood from the body

• Left= Receives oxygenated blood from the lungs

2 lower ventricles (‘little bellies’)

• Eject blood from the heart into arteries

• Right= Pumps deoxygenated blood to the lungs

• Left= Pumps oxygenated blood to the body

What do heart valves do?

control the direction of blood flow through the heart, ensuring it doesn't flow backward into the chambers

Why is the left side of the heart slightly larger than the right?

because it's responsible for pumping oxygen-rich blood to the rest of the body, requiring more powerful contractions

what are arteries?

large vessels transporting oxygenated blood

what are veins?

large vessels transporting deoxygenated blood

what are capillaries?

tiny blood vessels that are the location of oxygen exchange

What is a myocardial infarction and how does damage occur during one?

Blockages in vessels can have catastrophic consequences

when blood flow to the heart muscle is blocked, causing damage or death of heart tissue

what is the upper respiratory tract?

consists of the nose, nasal passages, sinuses, pharynx (throat), and larynx (voice box)

what is the lower respiratory tract?

consists of the structures below the vocal cords in the respiratory system, including the trachea, bronchi, and lungs

What does the diaphragm do during inhalation?

pushes downward, lowering intrapulmonary pressure

What does the diaphragm do during exhalation?

relaxes, raising intrapulmonary pressure

What is the primary function of the lymphatic system?

helps circulate bodily fluid

What are lymph nodes and why do they swell?

Tiny little filters

About 600 throughout lymphatic vessels

Large groups near the mammary glands, axillary and groin regions

swell due to infection

What are the components of the urinary system?

• Two kidneys

  • Filter blood plasma urine

• Two ureters

  • Transports urine from kidneys to bladder

• One urinary bladder

  • Stores urine until created

• One urethra

  • Carries urine from bladder to outside of body

What is the urinary system’s primary function?

• Adjusting blood composition

  • Regulating plasma concentrations of sodium, potassium, chloride, calcium, and phosphate ions

• Regulates blood volume

  • Water conservation vs excretion

• Waste removal

What are the components of the skeletal system?

bone, cartilage, and ligaments

How many bones does a human adult have?

206

What are the major functions of the male reproductive system?

produce sperm and semen, transport them, and produce and secrete male sex hormones, primarily testosterone

What do the testes produced?

sperm and hormones

Is sperm haploid or diploid once developed?

haploid

What process is used to make haploid sperm?

spermatogenesis, which includes meiosis

How long does it take for sperm to mature?

70 days

How does the sperm cell rearrange itself to be efficient for fertilization?

Nucleus moved

Cytoplasm mostly removed

Many organelles removed

Mitochondria rearranged